Hef celebrated his 84th birthday on April 9, 2010. We found a few of his most unforgettable, sexiest birthday moments from the past, including a nice surprise from Playmate legend Pamela Anderson and a song from Paris Hilton. See more of Hef’s past birthday moments at *******www.playboy****/articles/hugh-hefners-vegas-birthday-party-2009/index.html.